title: Fragile-X mental retardation in a large five-generation family. A clinical and cytogenetic study.
abstract: A number of problems concerning both clinical and genetic or cytogenetic aspects of the fragile-X syndrome remain unsolved. In the present work, a large 5-generation fragile-X family has been clinically and cytogenetically investigated. The results of our study indicated that an unusually high proportion of affected males was present in the family examined; all fragile-X-positive males were profoundly retarded and showed the phenotype typically described for this syndrome; moreover, we observed a variability of penetrance within the pedigree and all fragile-X-positive females in the 4th and 5th generation had some degree of mental impairment. A multistep mutation model has been proposed in order to explain some of these findings.
authors.affiliation: Dipartimento di Genetica e Microbiologia A. Buzzati Traverso, Università di Pavia, Italia.
authors.forename: E
authors.initials: E
authors.lastname: Raimondi
authors.forename: C
authors.initials: C
authors.lastname: Lenti
authors.forename: M
authors.initials: M
authors.lastname: Romagnoni
authors.forename: R
authors.initials: R
authors.lastname: Negri
authors.forename: E
authors.initials: E
authors.lastname: Gambini
authors.forename: L
authors.initials: L
authors.lastname: Musetti
authors.forename: L
authors.initials: L
authors.lastname: De Carli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D005600:Fragile X Syndrome / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D012729:Sex Chromosome Aberrations / Q000235:genetics*; D014960:X Chromosome / Q000032:analysis*